Brand really does not matter, so put that way low on your list.
Paasche and Badger are made in the US - according to many on this forum, that is a big deal.
As mentioned above, customer service/parts is important and you will probably need some. I'm a Badger user, but have not really had to use the service department, but I have purchased spare parts for when the time is needed to change them out. I'm sure Paasche is similar.
Air supply not so important as long as you have a moisture trap. Other than that, I agree that the cheap/loud ones are not fun to paint with. Spend a little more and have a good compressor for other uses around the house.
What are you painting? Just like regular paint brushes for different tasks, airbrushes are not one size fits all. Luckily, two airbrushes can cover most needs. One airbrush if you can target your needs, (basecoats, fine detail, thick paints (acrylics vs. solvent based) thin.
Not knowing what you want to paint, I would go for a double action brush and learn to use it. One of the big benefits to a double action brush is that you still release the air without shooting paint. This is a great feature to quick dry the paint between coats.
Charlie